The research now in progress and that planned under this research grant is based on detailed light microscopic, ultrastructural and immunopathologic studies of the kidney in human and experimental renal diseases. Studies of human renal diseases will be done on renal biopsy, nephrectomy and autopsy specimens and to a considerable extent are dependent on the type and amount of material made available through the clinical services. Ongoing investigations are directed primarily to Bence Jones Nephropathy, Renovascular Hypertension, Renal Allografts and Lupus Nephritis. The morphologic findings are correlated with clinical and laboratory data. Experimentally three major projects are either in progress or will begin during the year: 1. Glomerular capillary lesions, induced in rabbits by intrarenal artery perfusion with enzymes or vasoactive amines, are being studies to clarify their evolution and repair; 2. Renal arteriolar changes, induced in rats by DCA-salt or Goldblatt's hypertension, will be studied with particular attention to the prehypertensive phase and to the role of intravascular coagulation; 3. Further studies with the mouse model of Bence Jones cast nephropathy, developed in this laboratory, to investigate the role of related pathogenetic factors such as hypercalcemia and hydropenia.